1. Field of the Invention
The present invention relates to user interface technology of a game machine for realizing interactive games.
2. Description of the Related Art
In a game machine realizing so-called action type games and the like, a leading character (player character) within pictures of a game displayed on a display screen is controlled and the story of the game progresses in correspondence with control signals input via an input device (controller pad) controlled by a player.
With the recent improvement of performance of hardware in particular, the stage effect of such game is enhanced further by presenting game pictures in 3-D graphics which the player character acts within a virtual 3-D space.
Based on 3-D data rendering the object, the 3-D graphics renders an object in three dimensions by calculating the spatial positional relationship of the object existing in the direction of line of sight from the view point position (also referred to as xe2x80x9cthe projection center position) in the virtual 3-D space and by implementing image processing such as a rendering processing. That is, games utilizing the 3-D graphics present the game pictures rendering the virtual 3-D space by rendering the player character and other objects seen from the view point position in three dimensions and by moving the view point and the line of sight corresponding to the control made by the player or to scenes of the game. The picture of the game seen from such view point position is also called a camera angle by likening with an image taken by a camera.
An interest in such action type game or the like is often swayed by the pictures of the game rendered on the display in addition to the story of the game. Therefore, the type of game pictures to be presented to a player is a very important factor in producing a game (game program).
However, conventional games have presented game pictures rendering the virtual 3-D space only from a specific camera angle and could present no game picture seen from the optimum camera angle corresponding to the situation of the game.
For instance, there have been presented game pictures as if they are taken while continually tracking the character by a virtual camera disposed at the upper rear position of the character throughout the story of the game.
However, an enemy character approaching to the leading character from the back or an item disposed on the back could not be fully rendered in such game pictures from the specific camera angle, so the behavior of the enemy character had to be restricted on the game program so as not to attack from the back.
Further, when the character enters a narrow cave for example, the camera angle from the upper rear position theretofore is switched to the low angle seen from the position of the line of sight of the character.
However, the camera angle is only switched to a predetermined one when a specific scene or stage appears in such game and is not switched by judging the optimum angle corresponding to the situation of the game which changes in real-time.
One of the factors for increasing the interest in the game is to provide a game picture that enhances the stage effect of the game as described above.
However, conventional games provided only the game picture rendering the virtual 3-D space from the specific camera angle and are not able to select the optimum camera angle corresponding to the situation of the game or to provide a game picture of that camera angle.
Accordingly, it is an object of the invention to present pictures of a game for rendering a virtual 3-D space effectively corresponding to the situation of the game.
Further, there is a game which is capable of moving the character in a different direction from a specific direction within a virtual 3-D space while developing the story of the game by causing the character to advance in a specific direction.
However, the player looses a so-called sense of direction by loosing the direction in which the character is heading at such time when the direction in which the character is to head in the story of the game deviates from the present heading direction with the camera angle from the position of the light of sight of the character or from the upper rear position. Therefore, desired is a presentation of a game picture so as to indicate the direction in which the character is to head.
Another object of the invention is to present a game picture in which the player controlling the character within the virtual 3-D space rendered on the display will not loose the sense of direction within the virtual 3-D space.
Further, while the character moves in a direction instructed by a directional key of an input device, there is a case when the moving direction of the character in the game picture deviates from the instructed direction input via the input device when the character moves within the virtual 3-D space. For instance, when the path where the character goes along is looped, the character advances in the direction opposite from the direction in which the character is to move forward in game pictures on the path of the looped path even if the player manipulates the directional key in the forward direction (toward the far back of the game picture).
When the player switches the instructing direction of the directional key in accordance with the moving direction of the character on the game picture in such a case, the manipulation becomes very complicated and the player is confused.
Still an other object of the invention is to provide a game machine which simplifies the input manipulation of the input device by the player for moving the character within the virtual 3-D space rendered on the display.
The inventive game screen display controlling method comprises the steps of displaying a first game screen obtained from a first projection of a virtual 3-D space; comparing the priority of the first projection with the priority of a second projection correlated with a predetermined area when there is a predetermined positional relationship between a character (player character) who moves in the virtual 3-D space and the predetermined area set within the virtual 3-D space; and displaying a second game screen obtained from the second projection of the virtual 3-D space when the priority of the second projection is higher than the priority of the first projection.
Here, xe2x80x9cprojectionxe2x80x9d shall mean a view of the virtual 3-D space seen through a virtual camera and is given by various parameters such as the view point position, direction of line of sight and visual range (visual angle) of the virtual camera.
The predetermined area may be a plane set vertically to a plane of the field where the player character moves, a region of a predetermined shape on the plane of the field, a polygon or a sphere for example regardless of whether it is plane or 3-D.
A xe2x80x9cpredetermined positional relationshipxe2x80x9d shall mean the positional relationship when the player character touches the predetermined area or when the player character stays within the predetermined area.
The invention pertains also to the control of movement of the character in which an input direction of an input device with respect to a direction of visual recognition within the virtual 3-D space is correlated with the moving direction of the character within the virtual 3-D space and is characterized in that the moving direction of the character is decided based on predetermined path information correlated with a predetermined section when the player character moving in the virtual 3-D space stays within the predetermined section set in the virtual 3-D space.
Path information is data of a plurality of points to which position coordinates and directional information within the virtual 3-D space are given. According to the invention, point data is specified out of the path information based on the position coordinates of the character and the moving direction is decided based on the directional information given to the specified point data.
The invention described above also holds as a program for causing the game machine to realize the predetermined functions. The recording medium here includes a memory such as a RAM and a ROM besides a hard disk (HD), a DVD-ROM, a flexible disk (FD) and a CD-ROM for example. The computer includes a so-called microcomputer and, the like in which a so-called central processing unit such as a CPU and MPU implements predetermined processing by interpreting programs.
The invention of a product may be grasped as the invention of a method and vice versa.
The specific nature of the invention, as well as other objects, uses and advantages thereof, will clearly appear from the following description and from the accompanying drawings.